#1 Daniel Bryan

The Big Dog facing Daniel Bryan would be something fresh for the fans to see. The two faced off last time back in 2015 at WWE Fastlane, for an opportunity to face Brock Lesnar at WrestleMania 31 for the WWE Championship.
Besides that, Bryan and Reigns developed great chemistry when Reigns was in The Shield. WWE can use that chemistry to start a new rivalry between Reigns and Bryan.
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WWE can plan an interruption by Roman Reigns when Daniel Bryan is about to make his big announcement. In this way, the seeds for a long feud can be planted.
Both wrestlers are on SmackDown which means it has a high possibility of occurring. Bryan's direction is unclear after he lost the SmackDown Tag Team Championships at Extreme Rules, and Reigns does not have an opponent nailed down either.
If it is booked well, WWE can give the fans a classic rivalry.
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